Identifying of series resistance and interface states on rhenium/n-GaAs structures using C-V-T and G/-V-T characteristics in frequency ranged 50 kHz to 5 MHz


ÇİÇEK O., DURMUŞ H., ALTINDAL Ş.

JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS, vol.31, no.1, pp.704-713, 2020 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 31 Issue: 1
  • Publication Date: 2020
  • Doi Number: 10.1007/s10854-019-02578-1
  • Title of Journal : JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
  • Page Numbers: pp.704-713

Abstract

In this study, Re/n-GaAs with a native oxide layer based on metal-semiconductor (MS) structures were produced and then, the capacitance-voltage-temperature (C-V-T) and the conductance-voltage-temperature (G/-V-T) data of them were obtained in the frequency ranged 50 kHz to 5 MHz. Using the raw data, the electronic parameters was calculated by the developed LabVIEW-based program. Methodologically, the series resistance (R-s) values were calculated from the measured capacitance (C-m) and conductivity (G(m)) values, while the interface state (N-ss) values were obtained from using the combined high (C-HF)-low (C-LF) frequency capacitance method by Nicollian and Brews. Experimentally, the C values increased with a decreasing frequency, while decreased with increasing temperatures in the depletion and accumulation regions. On the other hand, G/ values decreased with increasing frequency in forward and reverse bias regions. It can be attributed that, the C and the G/ values are quite affected by the presence of the R-s and the N-ss in the forbidden energy gap and a native oxide layer between M and S. The R-s-V-T curves have especially peaks in accumulation and depletion regions at low frequency values, whereas these peaks decreased at high frequencies. In addition, the N-ss-V-T curves give peaks in the range of - 0.1 V to 0.7 V at variable temperatures and the N-ss values decrease with increasing temperature and shift towards negative bias regions. Experimental results indicate that the R-s and N-ss are important parameters and so, these parameters must be considered in sensor applications based on Re/n-GaAs structures.